But many are surprised by Houston's secrets, only discovered if given a tour by a resident.

ECONOMIST: Climate of change

Scientists have discovered the genetic secrets of a devastating disease that gradually robs healthy infant girls of their language, mental functioning and ability to interact with others.

BBC: News | Health | Scientists crack secret of child disease

Mr Savas has discovered matters too explosive to remain official secrets.

ECONOMIST: Turkey

Through Freud, dreams were then discovered as the voice of the subconscious, its inner secrets revealed through automatic writing or self-induced hypnosis (with Breton's first wife, Simone, assigned the women's role of note-taker).

ECONOMIST: 20th-century art